When preparing fat containing products, eg chocolate products, with the aid of moulds it is necessary to obtain the final product in a simple manner and without breakage. It is known to obtain chocolate products, in particular those in the form of shells, by introducing a mass of molten chocolate into a mould. After allowing that part of the chocolate mass in contact with the mould surface to solidify the mould is inverted and the remaining liquid mass falls in a reservoir. The resultant shell can then be removed from the mould or filled in situ. Another route to obtaining a chocolate shell is spin moulding in which a measured dose of chocolate is filled into one half of a hinged mould pair and the halves closed to complete the product shape. The closed mould is then spun on several axis to distribute the chocolate evenly on the mould wall where it solidifies to form a complete shell. After opening the mould, the resultant shell can then be removed or filled in situ through a small hole in the shell wall. However production lines of recent design require a supply of components which are of consistent quality, thus avoiding rework, and size and provided regularly at short time intervals. The inverting mould route does not provide chocolate products with these properties; spin moulding requires the shell to be filled through a small hole and thus the types of ingredients are limited.
The term "chocolate" is used herein generally to include fat based compositions having a chocolate component and extends to couvertures. Such compositions are well characterised in the literature, examples are Kirk-Othmer (2nd Edition, 1964) at pages 363 et seq and Elements of Food Technology page 579 et seq. There is a general problem is obtaining reproducible mould release when a product has to be released from two, or more, surfaces. Frequently the product will fail to separate cleanly from both surfaces so a broken product is obtained with consequent need to handle and rework.